Crafty Crows Can Build Tools From Memory

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iStock

Scientists have discovered yet another reason to never get on a crow's bad side. According to new research reported by Gizmodo, members of at least one crow species can build tools from memory, rather than just copying the behavior of other crows—adding to the long list of impressive skills that set these corvids apart.

For the new study, published in the journal Scientific Reports, an international team of scientists looked at New Caledonian crows, a species known for its tool usage. New Caledonian crows use sticks to pick grubs out of logs, sometimes stashing these twigs away for later. Tools are so important to their lifestyle that their beaks even evolved to hold them. But how exactly the crows know to use tools—that is, whether the behavior is just an imitation or knowledge passed down through generations—has remained unclear until now.

The researchers set up the experiment by teaching eight crows to drop pieces of paper into a box in exchange for food. The birds eventually learned that they would only be rewarded if they dispensed either large sheets of paper measuring 40-millimeters-by-60 millimeters or smaller sheets that were 15-millimeters-by-25 millimeters. After the crows had adapted and started using sheets of either size, all the paper was taken away from them and replaced with one sheet that was too big for the box.

The crows knew exactly what to do: They ripped up the sheet until it matched one of the two sizes they had used to earn their food before and inserted it into the dispenser. They were able to do this with out looking at the sheets they had used previously, which suggests they had access to a visual memory of the tools. This supports the "mental template matching" theory—a belief among some crow experts that New Caledonian crows can form a mental image of a tool just by watching another crow use it and later recreate the tool on their own, thus passing along the template to other birds including their own offspring.

This is the first time mental template matching has been observed in birds, but anyone familiar with crow intelligence shouldn't be surprised: They've also been known to read traffic lights, recognize faces, nurse grudges, and hold funerals for their dead.

[h/t Gizmodo]

The Time German and Russian WWI Soldiers Banded Together to Fight Wolves

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iStock.com/567185

During the winter of 1917, Russian and German soldiers fighting in the dreary trenches of the Great War’s Eastern Front had a lot to fear: enemy bullets, trench foot, frostbite, countless diseases, shrapnel, bayonets, tanks, sniper fire. Oh, and wolves.

In February of that year, a dispatch from Berlin noted that large packs of wolves were creeping from the forests of Lithuania and Volhynia into the interior of the German Empire, not far from the front lines. Like so many living creatures, the animals had been driven from their homes by the war and were now simply looking for something to eat. “As the beasts are very hungry, they penetrate into the villages and kill calves, sheep, goats, and other livestock,” the report, which appeared in the El Paso Herald, says. “In two cases children have been attacked by them.”

According to another dispatch out of St. Petersburg, the wolves were such a nuisance on the battlefield that they were one of the few things that could bring soldiers from both sides together. “Parties of Russian and German scouts met recently and were hotly engaged in a skirmish when a large pack of wolves dashed on the scene and attacked the wounded,” the report says, according to the Oklahoma City Times. “Hostilities were at once suspended and Germans and Russians instinctively attacked the pack, killing about 50 wolves.” It was an unspoken agreement among snipers that, if the Russians and Germans decided to engage in a collective wolf-hunt, all firing would cease.

Take this July 1917 New York Times report describing how soldiers in the Kovno-Wilna Minsk district (near modern Vilnius, Lithuania) decided to cease hostilities to fight this furry common enemy:

"Poison, rifle fire, hand grenades, and even machine guns were successively tried in attempts to eradicate the nuisance. But all to no avail. The wolves—nowhere to be found quite so large and powerful as in Russia—were desperate in their hunger and regardless of danger. Fresh packs would appear in place of those that were killed by the Russian and German troops.

"As a last resort, the two adversaries, with the consent of their commanders, entered into negotiations for an armistice and joined forces to overcome the wolf plague. For a short time there was peace. And in no haphazard fashion was the task of vanquishing the mutual foe undertaken. The wolves were gradually rounded up, and eventually several hundred of them were killed. The others fled in all directions, making their escape from carnage the like of which they had never encountered."

Afterward, the soldiers presumably returned to their posts and resumed pointing their rifles at a more violent and dangerous enemy—each other.

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